<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>

<body>
<script>
window.onload=function(){
	var btn=document.getElementById('btn');
	var oFrag=document.createDocumentFragment();
	var ul=document.getElementById('ul');
	btn.onclick=function(){
		var start=new Date().getTime();
		
		
		for(var i=0;i<20000;i++){
			var oLi=document.createElement('li');
			oFrag.appendChild(oLi);	
		};	
		ul.appendChild(oFrag);
		alert(new Date().getTime()-start);
	};
};	
	
	
	
</script>
<input type="button" value="碎片" id="btn" />
<ul id="ul">
</ul>
</body>
</html>
